1. Field of the Invention
The present invention relates to a tape-guide made from synthetic resin situated within, e.g. a magnetic tape cassette for a video recorder, a method of manufacturing the tape-guide, and an apparatus for manufacturing the tape-guide.
2. Description of the Related Art
In general, in a video recorder, a magnetic tape is employed as a recording medium for recording image signals. The magnetic tape is wound around a reel, and contained within a cassette. This type of magnetic tape is generally thin and made of a plastic material. The tape has a recording surface coated with magnetizable ferrite particles. A pair of tape-guides are disposed within the magnetic tape cassette. The tape-guides serve to guide the magnetic tape so that the recording surface of the magnetic tape may slide over a recording/reproducing magnetic head of the video recorder. In general, the tape-guide is put in direct contact with the rear surface (opposite to the recording surface) of the magnetic tape. The tape-guide must meet the following conditions:
1) The tape-guide is made of non-magnetic material for obtaining clear images,
2) The tape-guide has a smooth surface in order to allow the tape to run smoothly and to prevent deterioration (extension) of the tape, and
3) The surface of the tape-guide has a hardness of a predetermined value or more, in order to prevent damage to the tape.
Conventionally, these three conditions have been met by tape-guides made of processed metallic material. The metallic material is mainly brass or non-magnetic stainless steel which allows cutting and polishing with the surface precision of 0.2 to 0.8 .mu.m. When the tape-guide is made of brass, the Vickers hardness (VH) can be set to 800 to 900 by means of surface processing such as hard chrome plating. On the other hand, when the tape-guide is made of stainless steel, VH can be set to 350 to 400. Tape-guides made of such metallic materials can meet the above three conditions.
When the tape-guide is made of the aforementioned metallic material, however, five steps, i.e. material formation, polishing, plating, finish-polishing, and inspection/packaging, are necessary. Thus, a great deal of time is required to manufacture a finished product from a raw material, and special skill is required in a polishing step. Consequently, the manufacturing cost is increased.